I'm clueless as to which would be the better investment.
Current equipment:
350D
Kit lens (in my case, total garbage)
70-300mm f/4.9-5.6 IS USM (which I *just* found out last night falls into the "third number in serial number 0 or 1" category, so it will be sent for repair
nifty fifty ( LOVE that little cheapie)
Sigma 15-30mm f/3.5-4.5 EX Aspherical (Would like to sell)
Sigma 70-300 mm ( Bought that one the day I bought the camera. Still like it for Macro)
I would love to get the 5D, but (of course) I also want some premium lenses. I enjoy taking people photos and landscape, and would love to move on to portraiture.
Any help and just personal opinions appreciated.

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